<p>For other readers, here’s the relevant text from the MIT website:
“The vast majority of our admitted homeschool students have taken advantage of advanced classes outside the homeschool setting, such as through a local college or an online school such as EPGY. Transcripts of these courses, in addition to evaluation of the homeschooling portfolio, are very helpful. Some students will also take advantage of MIT’s OpenCourseWare.”</p>
<p>Given this language, I think it would be helpful to take a college-level mathematics class, preferably over the summer if you’re planning to apply Early Action. The simplest way to do this is through EPGY, though it’s pricey. You could look for a cc course in a science during the fall.</p>
<p>The phrase “The vast majority of our admitted homeschool students” makes me think that you have less to worry about if you have participated in well-known mathematics competitions, science olympiads, ISEF, or similar competitions and done well. If you are homeschooled as a prodigy and the parent teaching you is a well-known mathematician (it happens), then you may also not have much to worry about. But unless you have these achievements/qualities, you should take steps to demonstrate to MIT – and frankly, all the other top schools to which you will apply – that your education has been really rigorous.</p>